title: Influences on trimerization and aggregation of soluble, cleaved HIV-1 SOSIP envelope glycoprotein.
abstract: We describe methods to improve the properties of soluble, cleaved gp140 trimers of the human immunodeficiency virus type 1 (HIV-1) envelope glycoproteins (Env) for use in structural studies and as immunogens. In the absence of nonionic detergents, gp140 of the KNH1144 genotype, terminating at residue 681 in gp41 (SOSIP.681), has a tendency to form higher-order complexes or aggregates, which is particularly undesirable for structure-based research. We found that this aggregation in the absence of detergent does not involve the V1, V2, or V3 variable regions of gp120. Moreover, we observed that detergent forms micelles around the membrane-proximal external region (MPER) of the SOSIP.681 gp140 trimers, whereas deletion of most of the MPER residues by terminating the gp140 at residue 664 (SOSIP.664) prevented the aggregation that otherwise occurs in SOSIP.681 in the absence of detergent. Although the MPER can contribute to trimer formation, truncation of most of it only modestly reduced trimerization and lacked global adverse effects on antigenicity. Thus, the MPER deletion minimally influenced the kinetics of the binding of soluble CD4 and a CD4-binding site antibody to immobilized trimers, as detected by surface plasmon resonance. Furthermore, the MPER deletion did not alter the overall three-dimensional structure of the trimers, as viewed by negative-stain electron microscopy. Homogeneous and aggregate-free MPER-truncated SOSIP Env trimers are therefore useful for immunogenicity and structural studies.
authors.affiliation: Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, New York, USA.
authors.forename: Per Johan
authors.initials: PJ
authors.lastname: Klasse
authors.forename: Rafael S
authors.initials: RS
authors.lastname: Depetris
authors.forename: Robert
authors.initials: R
authors.lastname: Pejchal
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Julien
authors.forename: Reza
authors.initials: R
authors.lastname: Khayat
authors.forename: Jeong Hyun
authors.initials: JH
authors.lastname: Lee
authors.forename: Andre J
authors.initials: AJ
authors.lastname: Marozsan
authors.forename: Albert
authors.initials: A
authors.lastname: Cupo
authors.forename: Nicolette
authors.initials: N
authors.lastname: Cocco
authors.forename: Jacob
authors.initials: J
authors.lastname: Korzun
authors.forename: Anila
authors.initials: A
authors.lastname: Yasmeen
authors.forename: Andrew B
authors.initials: AB
authors.lastname: Ward
authors.forename: Ian A
authors.initials: IA
authors.lastname: Wilson
authors.forename: Rogier W
authors.initials: RW
authors.lastname: Sanders
authors.forename: John P
authors.initials: JP
authors.lastname: Moore
mesh_terms: D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal; D057134:Antibodies, Neutralizing; D001665:Binding Sites; D015704:CD4 Antigens / Q000737:chemistry; D003902:Detergents; D057809:HEK293 Cells; D015483:HIV Antibodies; D015699:HIV Envelope Protein gp120 / Q000737:chemistry / Q000235:genetics / Q000276:immunology; D015700:HIV Envelope Protein gp41 / Q000737:chemistry / Q000235:genetics / Q000276:immunology; D015497:HIV-1 / Q000737:chemistry* / Q000235:genetics / Q000276:immunology; D006801:Humans; D008854:Microscopy, Electron; D008969:Molecular Sequence Data; D055503:Protein Multimerization; D020836:Protein Structure, Quaternary; D011994:Recombinant Proteins / Q000737:chemistry; D017384:Sequence Deletion; D012995:Solubility; D054299:env Gene Products, Human Immunodeficiency Virus / Q000737:chemistry* / Q000235:genetics / Q000276:immunology
chemical_list: D000911:Antibodies, Monoclonal; D057134:Antibodies, Neutralizing; D015704:CD4 Antigens; D003902:Detergents; D015483:HIV Antibodies; D015699:HIV Envelope Protein gp120; D015700:HIV Envelope Protein gp41; D011994:Recombinant Proteins; D054299:env Gene Products, Human Immunodeficiency Virus; C514793:gp120 protein, Human immunodeficiency virus 1; C097729:gp140 envelope protein, Human immunodeficiency virus 1; C514787:gp41 protein, Human immunodeficiency virus 1; C076613:recombinant soluble CD4